William h



(N0-Model.) f

W. E. HUGHES 8u P. OEIELLY.V

PROCESS OP PEEPARING PHOSPHORIG ACID PROM BONES.

F'lElll Wl TN 55555- v n NVENTCJR.

N PETERS. Pham-Lnhugmpm. wnsrfngem u.

lINrrEn Sfratrns Armar Iill? Errea.

WILLIAM H. HUGHES, OF JOHNSTON, AND PHILIP ORIELLY, OF PROVIDENCE,

RHODE ISLAND.

PROCESS-OF PREPARING PHOSPHORIC ACID FROM BONES.

SPECIFICATION forming part of Letters Patent No. 258,423, dated May 23, 1882.

Application filed December 15, 1881.

To all whom it may concern:

Be it known that we, WlLLiAM H. HUGHES, of Johnston, in the county of Providence and State of Rhode Island, and PHILIP ORIELLY,

of Providence, in said county and State, have jointly invented new and useful Improvements in the Process of Preparing Pure Acid Phosphates and Phospho-ric Acid from Bones; and we do hereby declare that the following is a to full, clear, and exact description of our invenvention, which willenable others skilled in the artto which it appertaius to make and use the same.

We do not claim as new the process of treatlng burned or calcined bones with sulphuric acid as now used generally in lead or leadlined vessels or vessels lined with substances liable to be corroded by the acids used or developed in the process', vwhereby a proportion 2o of lead in combination or other result of corrosion is left in the resulting products to obtain acid phosphate, superphosphate of lime, or phosphoric acid; but we do claim the process for preparing phosphoric acid and acid phosphate hereinafter described, and by which such acid or phosphates are obtained free from contamination by the results of corrosion, and also free from certain organicimpurities found in acid phosphates or 'phosphoric acid prepared 3o from calcined bones by all other processes.

The bones are first purified and washed with warm water acidulated with about two per cent. of hydrochloric acid, and then dried. The bones are then calcined or burned, as iu the present use of the art, in a suitable furnace till about a grayish or nearly white color throughout and then ground till finely pulverized. The nelypulverized bones are then mixed with sulphuric acid and water in a ves- 4o sel or tank lined with silicate of soda, 0r any substance not chemically acted on by the acids used or developed,inproportions, by weight, of

two hundred and forty parts of pure water andr seventy parts of pure commercial sulphure acid to one hundred parts of the pulverized bones, the proportion of acid heilig variable according to the degree of perfection of the caleining process. If the bones are calcined to a clear white color throughout, the propor 5o tion may be as great as seventy-five parts.

(No model.)

The acid and water are mixed first, and the bone-powder is then added in small quantities from time to time, being stirred and mixed thoroughly till the whole mass is incorporated. The niixtureis then leftat restforabouttwentyfour hours, after which it is put intoa filter construeted of a suitable vessel lined with silicate ot'vsoda or some other substance notchemically acted on by the mixture and provided with a false bottom pierced with a series of small holes, with a clean cloth placed over these holes. On top of this cloth broken and pounded glass is placed to give an even layer about six inches in depth, and immediately over the glass is a covering of coarse cloth to prevent the clogging of the interstices of the filtering material. Above this cloth is placed the digested mass of bone-dust, acid, and water above described. To the filter may be attached a hy draulic or steam apparatus for forcing Water or steam through the mass, thus quickening audrenderingmoreeomplete the process. This process is a combination of leaching or lixiviation and filtering, and it tends to deliver the acidulated water in a purer state than any process heretofore used. The acid mixed with water filters into the space between the false and real bottoms of the flter,and is thence led into a reservoir constructed of suitable material lined with silicate of soda or some other substance not chemically acted on by the mixture. Theliquor is then allowed to settleabout ten hours,'\vl1en it is drawn off into a vessel lined with some substance not acted upon chemically thereby, and a current of pure hot air or superhcated steam is made to pass through it for about one and one-half hour. This aeration or steaming of the acidulated fluid drives off the sulphurct of hydrogen and various organic gaseous compounds resulting from the unburned animal matter in the bones that may remain in the fluid, and also causes a partial precipitation ot' the sulphate of lime before then held in thefluid. After the acidulated fluid is treated with superheated steam or hot air and allowed to cool and settle, it is filtered through cloth, after which to each gallon of the liquid having a specific gravity of 1.15 is added about four hundred and fifty grains of chlorate ot' potassa. The mixture is ther placed ill pans lilled with solne substance not chemically actedon by the mixture-as grallite ware or agate wareand placed ill all evenly heated furnace for the process of tillal evaporation arld fusion.

This process ot' evaporatioll and fusion is indispensable to obtain two results-filst, a colnplete precipitationof what snlphateot'lilne is left ill the mixture; and, second, it destroys alld carries off, as hereinafter described, all or garlic colnpoullds wllicll relnaill ill the solutioll up to this point, and which, if not thoroughly brokell up alld eradicated, will cause a fungus growth ill the phosphoric acid, and thus illlpair its vahle asan elelllellt of medicinal colnpounds. No one, to ollr knowledge, has heretofore succeeded in destroying tllese organic compounds. The heating of the furnace is colltillued till the contents of tlle pans are first evaporated to dryness, and afterward the heat being colltillued, fuse illto a liquid forlll. At this poillt the oxygen leaves the potassium elllorate alld destroys the organic matter contailled in the pans. Itis believed that the free oxygen operates by volatilization and precipitation to remove all relnaills ot'organic lnatter ill the colnpound, and the chlorine passes off ill the process, because nolle of either are to be foulld in the completed product', producing phosphoric acid free fronl organic and other impurities.

The oven alld apparatus we use ill this oper ation of evaporating alld subsequently` fusillg the contents ot' the pans are formed and construeted substantially as follows, reference being had to the accompanying drawings, ill whlch- Figure lis a top view of the furnace alld bellch, with partial sectioll through line y y ot' Fig. 2. Fig. 2 is a sectional view through lille w ar of Fig. l.

Similar letters refer to silnilar parts in the twotigures.

B B are bottolll tlues ullder the sole S ot' the furnace.

T T are top fines in the arch ofthe furnace, through which the heated gases from the fire return to the front elld of the furnace, thence to be led into the side flue, F, by which they are conducted to the chimney, thus heating the oven evenly tllrougllout. The fire is built at the end of the furnace opposite the chimney, and at the other elld thethles B B are led into the tlues T T.

D D D are sets of double doors, swinging open, as shown by dotted lilles ill sectional part of Fi fr. l.

H is a bench built as high as the sole ofthe furnace, and across which and the sole of the furllace are laid the sets of rails R lt 1t, constituting railroad-tracks, on each of which runs a car similar to C and consistillg of a truck 0r car body mounted ou wheels. On the truck is a platform, P, turnillg on a piu, N, in the center, and supported by friction wheels or rolls mounted in the top of the body of the GEII'.

The pans colltainillg the acid compound are placed on the platform P, alld the loaded car is rnll into the oven between the opened doors D, after which the doors are shut and the overl heated.

E is all escape-tine, through which pass the volatile products ofthe evaporation alld fusion ofthe contents ofthe pans.

The advantages of heating the pans alld contents ill sucll an ovell instead of heating them in kettles over a tire are, first, there is no danger of burning the bottom ot' the pans or kettles, the furnace being heated uniformly throughout; second, there is no need of stirring the contentsof thepans, they being heated uniformly on all sides; alld, third, there is no danger ot' the boiling over of the contents of the pans, thus saving the llecessity of a watchman or constant attelldallt, as well as the loss or waste consequent upon sucll boiling over.

After fusion has taken place, alld the pans alld contents have been sufficiently exposed to the heat ot' the oven, the car is drawn out by a hook or cllain alld ullloaded. While the pans are yet hot a suficient quantity of water is added to dissolve the acid containedin tlleln. The fluid in the pans is then emptied illto a suitable vessel lined with solne substance not chemically acted on by the acid, in which it is allowed to settle alld cool. It is then finally filtered through a glass pereolator filled with broken alld pounded glass, from which it cscapes a pure solution ot' phosphoric acid.

1t is evident that this same process can, by slight changes ot' ingredients, be used to make acid phosphates; or the phosphoric acid, lnade as described, can be united with a base to lllake sucll phosphates.

It is well known to chemists alld others conversallt with liquid phosphates that phosplloric acid, when extracted frolll bolle-asll by the processes hitllerto in use, contains a large quantity ot' organic matters ill solutiomwhich are carried illto the phosphates nl ade tllerefronl. These same organic matters are found in the phosphates lllade directly fronl the bone-ash. If noteradicated, tllis organic nlatter will cause a fungus alld other organic growth ill acidphosphate compounds, which greatly injures the same and ilnpairs their medicinal qualities. Tllese organic impurities are thoroughly eradicated froln the phosphoric acid and acid phos pilates m ade by the process we have described.

1t is obvious that thc above-detailed pro cess may be abbreviated by the omission ot' manyot' the comparativelyless importantsteps and still be productive of good results. Thus the omission of steaming or aeratillg, alld also of the cleansing of the bones before calcining, one or both, would still leave all effective process.

Having thus described alld explained our invention, we claim alld desire to secure by Letters Patent- 1. In the process of preparing phosphoric acid from bones, the treating caleincd bones by mixing them with sulphuric acid, leaching ICO IIO

IIS

the result, then heating the resulting products by the application of heat equally in all directions to substantial dryness and fusion and dissolving the last result, While hot, in water with successive ltrations at dift'erentsta ges ol' the process, substantially as herein described.

2. Treating liquid acid phosphates with chlorate of potassa or its equivalents, and subjecting the compound to a high degree of heat, as described, and for the purposes set forth.

3. In the process of preparing phosphoric acid from bones, the treating calcined bones by mixing them with sulphuric acid, leaching the result, treating the leached products with steam, then heating the resulting products by the application of heat equally in all directions to dryness or until fusion takes place, and dissolving the last result, while hot, in Water with successive ltrations at different stages of the process, substantially as herein described.

4. The Within-described process ot' obtaining phosphoric acid and acid phosphates from bones, consisting substantially of, first, washing the bones before calcination with Water 25 acidulated with hydrochloric acid, as described; second, calcining the bones; third, mixing the calcined bones, as described, with sulphuric acid and Water; fourth, filtering the mixture, as described; fifth, the treating of 3o the filtered result with hot air or steam; sixth, treating the result with chlorate of potassa and subjecting the same to heat, as described, in an evenly-heated furnace; seventh, the mixing the result with water and filtering 35 the same.

WILLIAM H. HUGHES. PHILIP ORIELLY.

Witnesses:

OSCAR L'APHAM, WELCOME A. GREENE. 

